Engine runs rough at cold startup and stalls most of the time MAF sensor is all over the place up and down.

1996 BUICK REGAL
189,000 MILES
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FIREMNTED
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1900 miles on the Original rebuilt engine (my dad was an ASE Mechanic for 35 years but got out of the business in 1996

I have already replaced the TPS, Temp., MAP, MAF, upstream o2 sensor.

Plugs and wires are new I have cleaned the grounds on the bell-housing I do see a ground with a 16-18 Ga. wire by the battery tray on the inner fender well that the bolt is so rusted I haven't had the time to remove and clean it! (could this be the problem)
Jun 14, 2012 at 3:16 AM
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JACOBANDNICKOLAS
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Check the IAC and check for vacuum leaks.
Jun 14, 2012 at 3:43 AM
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I have suspected the IAC but it has about 6 pins and I cant find anything on how to test it! No vacuum leaks! I forgot to add if I hold the throttle at 2000 RPM's and slowly reduce the RPM's the MAF sensor is stable at Idle!
Jun 14, 2012 at 4:04 AM
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FIREMNTED
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I'm getting my readings from a scanner!
Jun 14, 2012 at 4:07 AM